Cement Calculator

One cubic yard requires approximately 45 bags of 80-lb (36 kg) mix, 60 bags of 60-lb (27 kg) mix, or 90 bags of 40-lb (18 kg) mix. For metric: one cubic meter needs about 59 bags of 36 kg mix or 29 bags of 50 kg mix. These are pre-mixed bags containing cement, sand, and aggregate. For projects over 1 yd³ (0.76 m³), ready-mix delivery is more economical and ensures consistent quality.

Cement is the binding agent (powder) that hardens when mixed with water—it's just one ingredient. Concrete is the complete mixture: cement (10-15%), water (15-20%), sand (25-30%), and gravel (40-45%). Bagged "concrete mix" contains all ingredients pre-blended. Portland cement alone cannot be used for construction—it must be combined with aggregates. Understanding this distinction helps you order the correct materials for your project.

Cement bag prices vary globally: USA $5-8 per 80 lb bag; UK £5-8 per 25 kg; EU €4-7 per 25 kg; India ₹300-400 per 50 kg; Australia A$8-15 per 20 kg; Malaysia RM15-25 per 50 kg; South Africa R80-120 per 50 kg. Bulk cement for large projects costs less per unit. Prices fluctuate with fuel costs and demand. Always compare prices from multiple local suppliers.

For pre-mixed bags: add water gradually (about 3 liters per 25 kg bag) and mix until uniform consistency—not too wet or dry. Mix in a wheelbarrow, mixer, or on a clean surface. Work in batches you can use within 20-30 minutes. For hot weather, use cold water and work in shade. For cold weather (below 4°C/40°F), avoid pouring or use accelerators. Proper mixing ensures maximum strength and durability.

Portland cement Type I/II is standard for most residential projects. Type III is high-early-strength for cold weather. Type V resists sulfate damage in soil. Quick-setting cement hardens in 20-40 minutes for repairs. Masonry cement is for mortar and stucco. White cement is for decorative work. For most DIY projects, standard gray Portland or pre-mixed concrete bags work well. Check local building codes for specific requirements.

Properly mixed and cured concrete lasts 50-100+ years. Factors affecting longevity: water-cement ratio (lower is stronger), proper curing (keep moist 7 days), reinforcement for structural applications, and protection from freeze-thaw cycles. Unopened cement bags stay good for 3-6 months in dry storage; moisture exposure causes hardening. Quality installation matters more than material cost for long-term durability.